Engine starting mechanism



Aug. 6, 1935. J. 5. KAUFFMAN 2,010,255

ENGINE STARTING MECHANISM Filed Dec. 21, 1931 INVENTOR Jess e S Aaaf/Wm):

wlizz LMLUW M mm Patented Aug. 6, 1935 UNITED STATES PATENT OFFICE ENGINE STARTING MECHANISM Jesse S. Kauffman, Detroit, Mich. Application December 21, 1931, Serial No. 582,479 4 Claims. (01. 74-7) 5 starts. Various specific constructions of starters of this general type have been devised in all of which it is essential that the gears should be disengaged upon the initial movement of the engine under its own power. However, with many constructions no provision is made for insuring that the gears should remain out of mesh while the engine is in operation. Consequently the unintentionai pressing of the starting pedal when the engine is running may result in stripping the gears, thereby rendering the starting mechanism inoperative. Another defect is that through lack of lubrication or some other cause, the gears may fail-to fully disengage, or that the gears after being disengaged may rebound into engagement again. In either case there is danger of stripping the teeth.

It is the object of the invention to provide means for positively holding the gears out of mesh whenever the engine is in operation and to this end the invention consists in the construction as hereinafter set forth.

In the drawing:

Figure 1 is a longitudinal section through a portion of a starting mechanism showing my improvement applied thereto;

Figure 2 is a similar view showing a modified construction, and

Figure 3 is a similar view showing another modification.

With the construction illustrated in Figures 1 and 2, A is the motor, B the motor shaft having a threaded portion C. D is apinion sleeved upon the shaft B and internally threaded to engage the threaded portion C. E is a grooved collar formed integral with the pinion D and F is a forked lever having pins G for engaging the groove in the collar and adapted to place a friction thereon resisting rotation. H -is a gear wheel mounted on the fly wheel or other part of the engine and adapted for cooperation with the pinion D.

With the construction as thus far described, whenever the motor is energized by the closing of the starting switch (not shown) the pinion D will be moved axially on the shaft B into engagement with the gear wheel H. This movement is occasioned by the frictional resistance to the rotation of the pinion due to the engagement of the lever F with the grooved collar E, together with the resilient pressure of a spring (not shown) acting on'said lever and tending to move the pinion towards the gear wheel. The frictional resistance retards the rotation of the pinion so that the screw C rotates relative thereto and advances said pinion axially into mesh with the gear wheel H. As soon, however, as the motor starts thehigher angular speed of the shaft B and worm C will move the pinion in the reverse direction and out of engagement with the gear wheel H.

As has been stated, with such a mechanism there is nothing to positively hold the pinion out of engagement with the gear wheel which sometimes results in accidental re-engagement while the motor is running and the stripping of the gears. To prevent such a result I have devised the. following construction:

I is a suction motor, preferably a cylinder with a piston I therein, the cylinder being connected by a conduit J with the inlet manifold of the engine (not shown). The piston I is provided with a rod J which is connected to the arm F of the lever F. There is also provided a spring K which engages the piston to move the same in an outward direction and through the medium of the lever F placing the required friction for retarding the rotation of the pinion. However, the suction on the piston when the engine is in operation will overcome this spring and move the lever F in the opposite direction tending to withdraw the pinion from the gear wheel. Thus in'addition to the operation of the screw 0 for moving the pinion D out of mesh with the gear wheel H there is the actuation of the piston I operating through the lever F and F and collar E to effect a similar movement. Furthermore, the movement effected by the piston is not limited to merely disengaging the pinion from the gear wheel but can move the pinion further to provide ample clearance between the same and said gear wheel. It is also evident that the parts will be held in this position as long as the engine continues to operate and that the operation of the starting motor will be nonefiectiveto move the pinion into mesh with the gear wheel.

With the construction shown in Figure 2, the operation is substantially the same, the only difference being in the specific construction of the starter mechanism which includes a resiliently yieldable torque coupling L between the motor shaft and the screw threaded pinion shaft. Figure 3 illustrates the application of my improvement to still another type of starting mechanism, viz; one which is provided with a ratchet clutch M between the pinion D and collar E, which latter is connected by the spline N to the motor shaft B. With such constructions it is usually necessary to provide a mechanical connection between the starting pedal and the lever F so that the pinion D is mechanically moved into engagement with the gear wheel H in advance of the operation of the starting motor. With my improved construction I dispense with this element and use in place thereof a spring 0 acting upon the piston I and having sufiicient power and range to move said piston I, lever F, collar E and pinion D to interrnesh the latter withthe gear wheel H. Thus with the construction shown in Figure 3, the suction motor is of greater capacity and the spring 0 of greater power than with the similar parts and constructions previously described.

In the operation of the construction shown in Figure 3, the pinion D will normally be in mesh with the gear wheel I-I before the starting of the engine so that upon starting the motor it will immediately drive said gear wheel and start the engine. As soon as the engine is started, manifold suction operating on the piston I will actuate the same and the lever F thereby withdrawing the pinion D from mesh with the gear wheel H. However, the ratchet M permits the pinion D to rotate at the same peripheral speed as the gear wheel H during the slight interval before the pinion is withdrawn from mesh. When the engine is stopped and the suction is relieved, the spring 0 will again force the pinion D into engagement with the gear wheel H. In case the teeth of the pinion and gear wheel do not properly register to engage with each other, a spring P of relatively light tension interposed between the ratchet clutch M and the collar E will yield, but as soon as the starting motor is actuated and proper registration is obtained, tlm's forces the spring in full engagement with the gear wheel.

With all of the constructions above described the pinion is positively held out of mesh with the gear wheel when the engine is in operation. In all, the starting of the engine will positively withdraw the pinion from engagement with the gear wheel and with the construction last described, this is accomplished without the use of the screw.

What I claim as my invention is:

1. In an engine starter mechanism of the character described, a starting motor including an armature shaft, a driven gear wheel, a pinion sleeved upon and threadedlyengageable with the armature shaft of said starting motor, a lever having one end engaging said pinion, a suction motor having a piston connected to the other end of said lever, a spring normally urging said piston in an outward direction and placing through the medium of the lever aforesaid the required friction for retarding the rotation of the pinion upon starting of the motor whereby the pinion will automatically move into mesh with said gear wheel, andsaid suction motor operating when the engine is started to with-draw the pinion from the driven gear wheel and hold the same out of engagement therewith.

2. An engine starting mechanism including in combination a starting motor having a driving shaft; a driven engine gear; a pinion mounted for longitudinal movement with respect to said shaft and rotary movement therewith; a lever having one end co -acting with said pinion; a suction motor having a movable member; a positive connection between the other end of said lever and said movable member; resilient means cooperating With the movable member of said suction motor for normally urging the pinion through the medium of said lever toward enmeshment position with said engine gear; means interposed between said pinion and said driving shaft for completing a driving connection between the pinion and engine driven gear when the motor is energized, the movable member of the suction motor operating through said lever to urge the pinion out of engagement with the engine gear when the engine is started.

3. An engine starting mechanism of the character disclosed, comprising in combination: a starting motor including a driving shaft; a driven gear wheel; a pinion mounted for longitudinal movement with respect to the shaft; splines located between said pinion and said shaft for establishing a driving connection therebetween; a

lever having one end co-acting with said pinion; a suction motor having a movable member; a positive connection between the other end of said lever and said movable member; resilient means cooperating with the movable member of the suction motor for normally urging the driving pinion towar enmeshment position with the driven gear Wheel to establish a driving connection between said pinion and gear wheel when the starting motor is energized; said suction motor operating when the engine is started to effect disengagement v of the pinion with the driven gear wheel.

4. An engine starting mechanism of the character disclosed, comprising in combination: a starting motor including an armature shaft; a driven gear wheel; a driving pinion carried on said armature shaft for longitudinal movement with respect thereto; means between said pinion and armature shaft for establishing a driving connection therebetween; a pivoted lever having one end co-acting with said pinion; a suction motor having a movable piston; resilient means opposing movement of said piston in one direction; a positive connection between the other end of said lever and said piston; said resilient means acting on said lever to urge the driving pinion toward enmeshment with the driven gear wheel whereby driving connection is established between said pinion and gear wheel when the starting motor is energized, said piston operating when the engine is started to urge the pinion out of engagement with the driven gear.

JESSE S. KAUFF'MAN. 

